Magnetism
Magnets have fascinated humans since their discovery thousands of years ago, well before 600 BC. A unit on magnetism would be appropriate for students of any grade in elementary school. Teaching and learning about magnetism should be based on discovery and involve the use of hands-on activities. Also beneficial to teaching magnetism would be to show a video in which very powerful electromagnets, such the ones that lift up automobiles, are used.
To enable students to enjoy experimenting with magnets in a classroom setting, a teacher needs to have a class set of magnets, at least one magnet for every two students. Otherwise, students will be bored waiting for their turn or watching others do the activity! It is nice to have a matching set but it doesn’t really matter. If cost is an issue, magnets can be easily purchased at your local dollar store.
Students will need to document which materials are magnetic and which are not. This recording can be done on a piece of paper or on a handout created by the teacher. Students should also try to determine why certain materials are magnetic and others are not. (Items containing iron are magnetic.)
Suggested Materials
· Magnets – one for each pair of students
· Paper clips – a box full
· Tin foil – a roll
· Wooden objects – at least one for each pair of students
· Coins–one of each type for each pair of students
· Plastic spoons – one for each pair of students
· Metal spoons – one for each pair of students
· Screws – one for each pair of students
· Bolts – one for each pair of students
· Scraps of paper – one for each pair of students
· Iron filings (Caution: A. Don’t let students get these filings in eyes. B. Using iron filings tends to be messy.)
· Petri dishes – one per pair (optional)
A good way to play with iron filings is to have them sealed in a Petri dish.
After identifying which materials are magnetic and which are not, student can do activities to determine which magnets are more powerful. One way to determine magnet strength is to see how many paperclips strung together a magnet can lift. Again, results should be recorded and discussed. Have the students come up with a hypothesis as to what makes some magnets stronger than others. At this point, it would be an excellent idea to show students a diagram of a material where magnetized molecules (north/south) are arranged in an orderly way.
Safety Note: Although it is fun to play with very powerful magnets, be careful with these, as little fingers can get pinched!